Hello,
I have the same problem, have you found a solution?
Server
Windows 10 Professional x64
UniGui 1.50.0.1481
Delphi Tokyo 10.2.2
Client
Windows 7 Professional SP1 x32 <--- the problem is on the client side, if it's 64bit works fine. I can try with Windows SO x64 and Chrome 32bit.
Chrome 70.0.3538.110 (Official Build) (32 bit)
Screenshot attached
https://drive.google.com/file/d/19NRz6pdERmM1oeTzIFpHkOLE9c5F-csp/view?usp=sharing